Fluid analysis of various bodily fluids is commonly used in assessing a patient's health or diagnosing a medical condition. For example, blood cell analysis may provide an indication of a patient's overall health based on the number and characteristics of various types of blood cells, such as red blood cells, white blood cells and platelets. Various manual and automated techniques have been used, including measuring impedance or dynamic light scattering as particles or cells pass through a sensing area. Appropriate analysis requires chemical and physical preparation of cells within a sample which conditions the cells from a natural state to a form more conducive to a particular analysis technique.
Such cell preparation has included mixing fluid samples, such as whole blood, with various reagents. Mixing techniques have included shaking, stirring, and otherwise agitating fluid samples with reagents to create random interactions between particulate matter in the fluid samples, such as blood cells, and reagent fluids. To ensure sufficient interaction, techniques based on random interactions have needed to be performed for at least a minimum period of time so that the fluid sample and its particulate matter can thoroughly mix with the reagent fluids.